RHSA-2016:1756 - Security Advisory

Topic

An update for qemu-kvm-rhev is now available for Red Hat OpenStack Platform 8.0 (Liberty).

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

KVM (Kernel-based Virtual Machine) is a full virtualization solution for Linux on AMD64 and Intel 64 systems. The qemu-kvm-rhev package provides the user-space component for running virtual machines using KVM in environments managed by Red Hat Enterprise Virtualization Manager.

Security Fix(es):

• Quick Emulator(QEMU) built with the Block driver for iSCSI images support (virtio-blk) is vulnerable to a heap-based buffer overflow issue. The flaw could occur while processing iSCSI asynchronous I/O ioctl(2) calls. A user inside a guest could exploit this flaw to crash the QEMU process resulting in denial of service, or potentially leverage it to execute arbitrary code with QEMU-process privileges on the host. (CVE-2016-5126)
• Quick Emulator(QEMU) built with the virtio framework is vulnerable to an unbounded memory allocation issue. It was found that a malicious guest user could submit more requests than the virtqueue size permits. Processing a request allocates a VirtQueueElement results in unbounded memory allocation on the host controlled by the guest. (CVE-2016-5403)

Red Hat would like to thank hongzhenhao (Marvel Team) for reporting CVE-2016-5403.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

After installing this update, shut down all running virtual machines. Once all virtual machines have shut down, start them again for this update to take effect.

Affected Products

• Red Hat OpenStack 8 x86_64

Fixes

• BZ - 1340924 - CVE-2016-5126 Qemu: block: iscsi: buffer overflow in iscsi_aio_ioctl
• BZ - 1358359 - CVE-2016-5403 Qemu: virtio: unbounded memory allocation on host via guest leading to DoS

CVEs

• CVE-2016-5126
• CVE-2016-5403

References

• http://www.redhat.com/security/updates/classification/#normal